My husband picked this up at an Antique shop for a few bucks. It was marked “Cast Iron Pirate Bookend” but there was only 1. We’ve tried to research it and so far it seems it could be Nuart but all the others we’ve found have solid backs- this one is hollowed. Also, its hard to see, but it seems that CGS could be imprinted on the back. I’m not sure what its made from or if it was other metal melted down, but it has a lot of pictures/writings on it when looked at under a certain angle under light with a magnifying glass. Any ideas?